Wilsonian Effective Action of Superstring Theory

TL;DR

This paper constructs a Wilsonian effective action for light fields in superstring theory by integrating out heavy fields, ensuring UV finiteness and exact scattering amplitude reproduction, while maintaining algebraic structures and BV quantum master equation compliance.

Contribution

It provides a systematic method to derive a manifestly UV finite Wilsonian effective action for light fields in superstring theory, preserving algebraic structures and exact amplitudes.

Findings

Effective action inherits algebraic structures of parent theory

Automatic satisfaction of BV quantum master equation

Reproduces exact scattering amplitudes of light states

Abstract

By integrating out the heavy fields in type II or heterotic string field theory one can construct the effective action for the light fields. This effective theory inherits all the algebraic structures of the parent theory and the effective action automatically satisfies the Batalin-Vilkovisky quantum master equation. This theory is manifestly ultraviolet finite, has only light fields as its explicit degrees of freedom, and the Feynman diagrams of this theory reproduce the exact scattering amplitudes of light states in string theory to any arbitrary order in perturbation theory. Furthermore in this theory the degrees of freedom of light fields above certain energy scale are also implicitly integrated out. This energy scale is determined by a particular parameter labelling a family of equivalent actions, and can be made arbitrarily low, leading to the interpretation of the effective action as the Wilsonian effective action.